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The Washington County Lead District Site consists of high concentrations of lead contamination from mining. The ore would normally be hauled from the mines to the concentrators (also known as mills) were it was formed into lead concentrate. Lead concentrate at the site was/is derived from the physical concentration of lead sulfide ore and is typically 70 to 80 percent (700,000 to 800,000 parts per million [ppm]) lead sulfide.
The primary problem areas at this site which require action are lead contaminated soils in yards, contaminated drinking water, and lead contaminated dust in homes along roadways.
The Washington County Lead District – Old Mines Site is located in a heavily mined region of eastern Missouri known as the Washington County Lead District. The Old Mines Site primarily includes residential areas within and around the communities of Old Mines, Kingston, Fertile, Tiff and other smaller communities, and is only a portion of the larger Washington County Lead Mining District.
Mines in the Old Mines Area include the following:
Pfizer Kingston School
Mobar Star Mine
MilchemWhale-Scott Mine
AW Wood Mine
DeSoto Mining Company – Fertile Mine
Dresser minerals Big River
Milchem Sun Mine
General Barite Blackwell
Dresser Minerals Mine #44
Dresser Minerals Racola
H&P Mining Company
General Barite Old Mines
Terrace Mines
Pfizer Arnault School
Dresser Minerals Breton Creek #3
Dresser Minerals Mine #11
NL Bariod Blackwell
Dresser Minerals Mine #6
In August 2005, EPA began an integrated assessment, which included soil and groundwater sampling in the Old Mines area. During this sampling event, EPA sampled the soil at 85 residences located on or near mining or mine waste disposal areas. Based on this data, approximately 47% of these residential properties had soils which exceeded 400 ppm and roughly 13% had soils which exceeded 1200 ppm for lead. EPA also sampled approximately 77 private drinking water wells in the Old Mines area beginning in August 2005. Of these 77 wells sampled, 7 exceeded 15 parts per billion (ppb) for lead, and one well exceeded 3030 ppb for barium, which exceeds the Maximum Contaminant Levels (MCLs) for lead and barium in drinking water.
EPA continues to sample residential soils and drinking water wells in the Old Mines area. Thus far EPA has sampled 490 properties, of which:
33 have soil lead levels greater than 1200 ppm
119 have soil lead levels between 400 and 1199 ppm
338 have soil lead levels less than 400 ppm
45 drinking water wells exceed the removal action level and residents are being provided bottled water.
EPA is attempting to locate an area for a repository for the excavated yard soils. Indian Creek Mine Site is being considered for the repository and discussions are ongoing. The site is owned by Doe Run and is a 200 plus acre tailings pile.
If an agreement can be reached by all parties to use the Indian Creek Mine Site as a repository, excavation of contaminated yard soils will begin. Otherwise a decision for an alternative disposal location will be made.
Continue sampling of residential soil and drinking water. Locate soil disposal facility.
Inability in locating a soil repository has delayed excavation of contaminated soil.
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